新型索梁结构应急桥车桥耦合振动分析  

ANALYSIS ON VEHICLE-BRIDGE-COUPLING VIBRATION OF A NEW TYPE OF CABLE-GRIDER EMERGENCY BRIDGES

作　　者：杨磊[1] 邵飞 江克斌 YANG Lei;SHAO Fei;JIANG Kebin(College of Military Basic Education,National University of Defence Technology,Changsha 410072,China;College of Field Engineering,Army Engineering University of PLA,Nanjing 210007,China)

机构地区：[1]国防科技大学军事基础教育学院,长沙410072 [2]陆军工程大学野战工程学院,南京210007

出　　处：《工业建筑》2020年第10期76-86,93,共12页Industrial Construction

基　　金：国防科技大学科研计划项目(ZK20-50)。

摘　　要：考虑索梁结构应急桥结构质量轻、刚度小的特点,车桥耦合振动问题值得研究。采用空间三轴车辆模型,基于动力平衡理论和有限元法建立车辆和桥梁的动力微分方程,应用Newmark-β法求解动力微分方程。采用APDL语言编写车桥耦合振动程序,分析连接、车速、车辆质量、路面等级等参数对桥梁结构振动响应的影响。结果表明:主梁铰接连接对于索梁结构应急桥结构车桥耦合振动响应有很大的影响,尤其对竖向位移及吊杆轴向应力影响显著;随车速的增大,桥跨不同位置动力响应峰值变化趋势不同,但均值响应基本呈增加趋势;路面等级对桥梁各项动力响应均有较大影响,对竖向加速度影响尤为显著;随着车辆质量的增加,桥梁结构各项动力响应均增大;桥梁结构阻尼的增加会对结构动力响应有一定程度的减小,但降低幅值不大,作用不显著。通过分析可知,为保障安全,该桥车辆通行时车辆质量不可超过30 t,车速不超过30 km/h,若需提高保障能力,需进一步改进桥梁结构方案。In view of light weight and small stiffness of the new type of cable-grider emergency bridges,vehicle-bridge coupling vibration is worth studying.The vibration differential equations of the vehicle-bridge system were established by the dynamic equilibrium theory and finite element method,and the Newmark-βmethod was used to solve the differential equations.Analysis programs of vehicle-bridge coupling vibration programming by APDL language in ANSYS,to analyse the dynamic responses of bridges in different connection types of main girders,vehicle speeds,vehicle masses,road surface grades and damping ratios of the bridge.The results indicated that connection types of main girders had a significant impact on vibration responses of bridges,especially on vertical vibration displacement and axial stress of suspenders.With the vehicle velocity increase,although the peak reponses of different location in grider spans were of different trends,the mean responses of vibration increased fundamentally.The dynamic responses of bridges kept close relationships with road surface grade of of bridges,especially with vertical vibration acceleration.With the vehicle-weight increase,the dynamic responses increased linearly.The dynamic responses decreased with the increase of damping ratios of bridges,but the amplitudes changed slightly.The analysis revealed that the vehicle weight could not exceed 30 tons and the vehicle speed coult not exceed 30 km/h.The scheme of emergency bridges needed further improvement if the safeguard capacity needed to be increase.

关 键 词：应急桥 路面不平整度 铰接 NEWMARK-Β法 车桥耦合振动 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]